LOS ANGELES -- Country music trio the Dixie Chicks, still taking heat for criticizing President Bush, are weathering sluggish ticket sales in several cities for their upcoming U.S. tour, industry watchers reported Thursday. While early ticket purchases for their first major tour in three years are generally robust in Northeastern cities, initial sales have fallen short of expectations in numerous markets, especially in the Midwest and South, forcing some dates to be scrubbed. According to Pollstar, dates in Memphis, Tennessee, Oklahoma City, Indianapolis, and Fresno, California, have been dropped from the tour schedule for now, while box-office sales also were...